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1.
J Am Coll Cardiol ; 81(6): 574-586, 2023 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-36585350

RESUMO

BACKGROUND: Mental illness among physicians is an increasingly recognized concern. Global data on mental health conditions (MHCs) among cardiologists are limited. OBJECTIVES: The purpose of this study was to investigate the global prevalence of MHCs among cardiologists and its relationships to professional life. METHODS: The American College of Cardiology conducted an online survey with 5,931 cardiologists globally in 2019. Data on demographics, practice, MHC, and association with professional activities were analyzed. The P values were calculated using the chi-square, Fischer exact, and Mann-Whitney U tests. Univariate and multivariate logistic regression analysis determined the association of characteristics with MHC. RESULTS: Globally, 1 in 4 cardiologists experience any self-reported MHC, including psychological distress, or major or other psychiatric disorder. There is significant geographic variation in MHCs, with highest and lowest prevalences in South America (39.3%) and Asia (20.1%) (P < 0.001). Predictors of MHCs included experiencing emotional harassment (OR: 2.81; 95% CI: 2.46-3.20), discrimination (OR: 1.85; 95% CI: 1.61-2.12), being divorced (OR: 1.85; 95% CI: 1.27-2.36), and age <55 years (OR: 1.43; 95% CI: 1.24-1.66). Women were more likely to consider suicide within the past 12 months (3.8% vs 2.3%), but were also more likely to seek help (42.3% vs 31.1%) as compared with men (all P < 0.001). Nearly one-half of cardiologists reporting MHCs (44%) felt dissatisfied on at least one professional metric including feeling valued, treated fairly, and adequate compensation. CONCLUSIONS: More than 1 in 4 cardiologists experience self-reported MHCs globally, and the association with adverse experiences in professional life is substantial. Dedicated efforts toward prevention and treatment are needed to maximize the contributions of affected cardiologists.


Assuntos
Cardiologistas , Cardiologia , Transtornos Mentais , Masculino , Humanos , Feminino , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Saúde Mental , Cardiologistas/psicologia , Prevalência , Transtornos Mentais/epidemiologia
2.
Cancers (Basel) ; 14(11)2022 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-35681762

RESUMO

To investigate a potential role for galectins as biomarkers that enable diagnosis or prognostication of breast or non-small cell lung cancer, the serum levels of galectins -1, -3, -7, -8, and -9 of cancer patients determined by ELISA assays were compared to the mutation status of 50 known cancer-critical genes, which were determined using multiplex PCR in tumors of the same patients. Mutations in the KIT proto-oncogene, which codes for the c-Kit protein, a receptor tyrosine kinase, correlated with higher levels of galectins -1, -3, -8, and -9 in breast cancer patients and galectin-1 in non-small cell lung cancer patients. Mutations in the KIT gene were more likely found in brain metastases from both of these primary cancers. The most common KIT mutation in our panel was p.M541L, a missense mutation in the transmembrane domain of the c-Kit protein. These results demonstrate an association between KIT oncogenic signaling and elevated serum galectins in patients with metastatic disease. Changes in protein trafficking and the glycocalyx composition of cancer cells may explain the observed alterations in galectin expression. This study can be useful for the targeted selection of receptor tyrosine kinase and galectin inhibitor anti-cancer treatments.

3.
Global Health ; 17(1): 99, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479570

RESUMO

BACKGROUND: Global health education partnerships should be collaborative and reciprocal to ensure mutual benefit. Utilisation of digital technologies can overcome geographic boundaries and facilitate collaborative global health learning. Global Health Classroom (GHCR) is a collaborative global health learning model involving medical students from different countries learning about each other's health systems, cultures, and determinants of health via videoconference. Principles of reciprocity and interinstitutional partnership informed the development of the GHCR. This study explores learning outcomes and experiences in the GHCR between students from New Zealand and Samoa. METHODS: This study used a mixed methods approach employing post-GHCR questionnaires and semi-structured face-to-face interviews to explore self-reported learning and experiences among medical students in the GHCR. The GHCR collaboration studied was between the medical schools at the University of Otago, New Zealand and the National University of Samoa, Samoa. RESULTS: Questionnaire response rate was 85% (74/87). Nineteen interviews were conducted among New Zealand and Samoan students. Students reported acquiring the intended learning outcomes relating to patient care, health systems, culture, and determinants of health with regards to their partner country. Interview data was indicative of attitudinal changes in relation to cultural humility and curiosity. Some reported a vision for progress regarding their own health system. Students in the GHCR reported that learning with their international peers in the virtual classroom made learning about global health more real and tangible. The benefits to students from both countries indicated reciprocity. CONCLUSIONS: This study demonstrates GHCR to be a promising model for collaborative and reciprocal global health learning using a student-led format and employing digital technology to create a virtual classroom. The self-reported learning outcomes align favourably with those recommended in the literature. In view of our positive findings, we present GHCR as an adaptable model for equitable, collaborative global health learning between students in internationally partnered institutions.


Assuntos
Estudantes de Medicina , Saúde Global , Educação em Saúde , Humanos , Aprendizagem , Nova Zelândia
9.
J Geriatr Cardiol ; 13(9): 727-732, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27899936
11.
Am J Physiol Heart Circ Physiol ; 298(2): H424-32, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19933419

RESUMO

This study utilized a transgenic mouse model that expresses an inducible dominant-negative mutation of the transforming growth factor (TGF)-beta type II receptor (DnTGFbetaRII) to define the structural and functional responses of the left ventricle (LV) to pressure-overload stress in the absence of an intact TGF-beta signaling cascade. DnTGFbetaRII and nontransgenic (NTG) control mice (male, 8-10 wk) were randomized to receive Zn(2+) (25 mM ZnSO(4) in drinking H(2)O to induce DnTGFbetaRII gene expression) or control tap H(2)O and then further randomized to undergo transverse aortic constriction (TAC) or sham surgery. At 7 days post-TAC, interstitial nonmyocyte proliferation (Ki67 staining) was greatly reduced in LV of DnTGFbetaRII+Zn(2+) mice compared with the other TAC groups. At 28 and 120 days post-TAC, collagen deposition (picrosirius-red staining) in LV was attenuated in DnTGFbetaRII+Zn(2+) mice compared with the other TAC groups. LV end systolic diameter and end systolic and end diastolic volumes were markedly increased, while ejection fraction and fractional shortening were significantly decreased in TAC-DnTGFbetaRII+Zn(2+) mice compared with the other groups at 120 days post-TAC. These data indicate that interruption of TGF-beta signaling attenuates pressure-overload-induced interstitial nonmyocyte proliferation and collagen deposition and promotes LV dilation and dysfunction in the pressure-overloaded heart, thus creating a novel model of dilated cardiomyopathy.


Assuntos
Cardiomiopatia Dilatada/fisiopatologia , Coração/fisiopatologia , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/antagonistas & inibidores , Vasodilatação/fisiologia , Disfunção Ventricular Esquerda/fisiopatologia , Animais , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/patologia , Proliferação de Células , Colágeno/metabolismo , Modelos Animais de Doenças , Fibroblastos/patologia , Coração/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Receptor do Fator de Crescimento Transformador beta Tipo II , Receptores de Fatores de Crescimento Transformadores beta/genética , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteínas Smad/metabolismo , Fatores de Tempo , Fator de Crescimento Transformador beta/metabolismo , Disfunção Ventricular Esquerda/metabolismo , Disfunção Ventricular Esquerda/patologia , Sulfato de Zinco/farmacologia
12.
Am J Physiol Heart Circ Physiol ; 297(2): H866-73, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19561306

RESUMO

Systemic inflammation induces a multiple organ dysfunction syndrome that contributes to morbidity and mortality in septic patients. Since increasing plasma apolipoprotein A-I (apoA-I) and HDL may reduce the complications of sepsis, we tested the hypothesis that the apoA-I mimetic peptide 4F confers similar protective effects in rats undergoing cecal ligation and puncture (CLP) injury. Male Sprague-Dawley rats were randomized to undergo CLP or sham surgery. IL-6 levels were significantly elevated in plasma by 6 h after CLP surgery compared with shams. In subsequent studies, CLP rats were further subdivided to receive vehicle or 4F (10 mg/kg) by intraperitoneal injection, 6 h after sepsis induction. Sham-operated rats received saline. Echocardiographic studies showed a reduction in left ventricular end-diastolic volume, stroke volume, and cardiac output (CO) 24 h after CLP surgery. These changes were associated with reduced blood volume and left ventricular filling pressure. 4F treatment improved blood volume status, increased CO, and reduced plasma IL-6 in CLP rats. Total cholesterol (TC) and HDL were 79 +/- 5 and 61 +/- 4 mg/dl, respectively, in sham rats. TC was significantly reduced in CLP rats (54 +/- 3 mg/dl) due to a reduction in HDL (26 +/- 3 mg/dl). 4F administration to CLP rats attenuated the reduction in TC (69 +/- 4 mg/dl) and HDL (41 +/- 3 mg/dl) and prevented sepsis-induced changes in HDL protein composition. Increased plasma HDL in 4F-treated CLP rats was associated with an improvement in CO and reduced mortality. It is proposed that protective effects of 4F are related to its ability to prevent the sepsis-induced reduction in plasma HDL.


Assuntos
Apolipoproteína A-I/imunologia , Inflamação , Peptídeos/farmacologia , Sepse , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/imunologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/imunologia , Volume Sanguíneo/efeitos dos fármacos , Volume Sanguíneo/imunologia , Ecocardiografia , Inflamação/tratamento farmacológico , Inflamação/imunologia , Inflamação/mortalidade , Interleucina-6/sangue , Lipoproteínas HDL/sangue , Masculino , Mimetismo Molecular/imunologia , Peptídeos/imunologia , Ratos , Ratos Sprague-Dawley , Sepse/tratamento farmacológico , Sepse/imunologia , Sepse/mortalidade , Volume Sistólico/efeitos dos fármacos , Volume Sistólico/imunologia
13.
Am J Physiol Heart Circ Physiol ; 295(1): H335-42, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18469144

RESUMO

Inflammation plays a major role in vascular disease. We have shown that leukocyte infiltration and inflammatory mediator expression contribute to vascular remodeling after endoluminal injury. This study tested whether increasing protein O-linked-N-acetylglucosamine (O-GlcNAc) levels with glucosamine (GlcN) and O-(2-acetamido-2-deoxy-d-glucopyranosylidene) amino-N-phenylcarbamate (PUGNAc) inhibits acute inflammatory and neointimal responses to endoluminal arterial injury. Ovariectomized rats were treated with a single injection of GlcN (0.3 mg/g ip), PUGNAc (7 nmol/g ip) or vehicle (V) 2 h before balloon injury of the right carotid artery. O-GlcNAc-modified protein levels decreased markedly in injured arteries of V-treated rats at 30 min, 2 h, and 24 h after injury but returned to control (contralateral uninjured) levels after 14 days. Both GlcN and PUGNAc increased O-GlcNAc-modified protein levels in injured arteries compared with V controls at 30 min postinjury; the GlcN-mediated increase persisted at 24 h but was not evident at 14 days. Proinflammatory mediator expression increased markedly after injury and was reduced significantly (30-50%) by GlcN and PUGNAc. GlcN and PUGNAc also inhibited infiltration of neutrophils and monocytes in injured arteries. Chronic (14 days) treatment with GlcN reduced neointima formation in injured arteries by 50% compared with V controls. Acute GlcN and PUGNAc treatment increases O-GlcNAc-modified protein levels and inhibits acute inflammatory responses in balloon-injured rat carotid arteries; 14 day GlcN treatment inhibits neointima formation in these vessels. Augmenting O-GlcNAc modification of proteins in the vasculature may represent a novel anti-inflammatory and vasoprotective mechanism.


Assuntos
Acetilglucosamina/análogos & derivados , Anti-Inflamatórios/farmacologia , Artérias Carótidas/efeitos dos fármacos , Lesões das Artérias Carótidas/tratamento farmacológico , Glucosamina/farmacologia , Mediadores da Inflamação/metabolismo , Oximas/farmacologia , Fenilcarbamatos/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Acetilglucosamina/farmacologia , Animais , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Lesões das Artérias Carótidas/metabolismo , Lesões das Artérias Carótidas/patologia , Modelos Animais de Doenças , Feminino , Glicosilação , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Infiltração de Neutrófilos/efeitos dos fármacos , Ovariectomia , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
14.
Echocardiography ; 25(2): 217-27, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18269568

RESUMO

BACKGROUND: Patent foramen ovale (PFO) is a well-recognized risk factor for ischemic strokes. The true prevalence of PFO among stroke patients is still under debate. Transesophageal echocardiography (TEE) is the "gold standard" in diagnosing PFO but the physiology requires right-to-left atrial shunting. In this report, we evaluate the prevalence of PFO in a diverse group of ischemic stroke patients studied by TEE. METHODS: TEE of 1,663 ischemic stroke patients were reviewed for cardiac source of embolism, including PFO and atrial septal aneurysm (ASA). Agitated saline bubble injection was performed to look for right to left atrial shunting. Success of maneuvers to elevate right atrial pressure (RAP) was noted by looking at the atrial septal bulge. RESULTS: Among 1,435 ischemic stroke patients analyzed, the presence or absence of PFO could not be determined in 32.1% because bulging of the septum could not be demonstrated in patients with negative contrast study despite aggressive maneuvers to elevate RAP. Of the remaining 974 patients, 294 patients (30.2%) had a PFO. The mean age was 61.5 years in both groups, with a bimodal distribution of PFO and the highest prevalence occurring in < or =30-year-old group. Prevalence of PFO was similar in men (32.4%) and women (28.15%, P = 0.15); and in Caucasian (32.1%) and African American (27.7%; P = 0.15). ASA was present in 2.02% and hypermobile septum in 2.49% of the 1,435 patients. PFO was seen in 79.3% of the patients with ASA. CONCLUSION: Successful elevation of RAP cannot be achieved in a significant number of patients undergoing TEE and determination of PFO may be difficult. In our series, the true prevalence of PFO among ischemic stroke patients was 30.2% taking into account only those patients who showed no shunting despite bulging of the atrium septum into the left atrium (PFO absent group) during the contrast study. There was no gender or racial difference in the prevalence of PFO, but there was a bimodal distribution in prevalence with age.


Assuntos
Forame Oval Patente/epidemiologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/etiologia , Distribuição de Qui-Quadrado , Ecocardiografia Transesofagiana , Feminino , Forame Oval Patente/diagnóstico por imagem , Forame Oval Patente/etnologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Fatores Sexuais
15.
Biogerontology ; 9(3): 139, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18185980

RESUMO

Changes in the levels of O-linked N-acetyl-glucosamine (O-GlcNAc) on nucleocytoplasmic protein have been associated with a number of age-related diseases such as Alzheimer's and diabetes; however, there is relatively little information regarding the impact of age on tissue O-GlcNAc levels. Therefore, the goal of this study was to determine whether senescence was associated with alterations in O-GlcNAc in heart, aorta, brain and skeletal muscle and if so whether there were also changes in the expression of enzymes critical in regulating O-GlcNAc levels, namely, O-GlcNAc transferase (OGT), O-GlcNAcase and glutamine:fructose-6-phosphate amidotransferase (GFAT). Tissues were harvested from 5- and 24-month old Brown-Norway rats; UDP-GlcNAc, a precursor of O-GlcNAc was assessed by HPLC, O-GlcNAc and OGT levels were assessed by immunoblot analysis and GFAT1/2, OGT, O-GlcNAcase mRNA levels were determined by RT-PCR. In the 24-month old animals serum insulin and triglyceride levels were significantly increased compared to the 5-month old group; however, glucose levels were unchanged. Protein O-GlcNAc levels were significantly increased with age (30-107%) in all tissues examined; however, paradoxically the expression of OGT, which catalyzes O-GlcNAc formation, was decreased by approximately 30% in the heart, aorta and brain. In the heart increased O-GlcNAc was associated with increased UDP-GlcNAc levels and elevated GFAT mRNA while in other tissues we found no difference in UDP-GlcNAc or GFAT mRNA levels. These results demonstrate that senescence is associated with increased O-GlcNAc levels in multiple tissues and support the notion that dysregulation of pathways leading to O-GlcNAc formation may play an important role in the development of age-related diseases.


Assuntos
Acetilglucosamina/metabolismo , Envelhecimento/metabolismo , Aorta/metabolismo , Encéfalo/metabolismo , Músculo Esquelético/metabolismo , Miocárdio/metabolismo , Proteínas/metabolismo , Acetilglucosamina/genética , Animais , Sequência de Bases , Cromatografia Líquida de Alta Pressão , Primers do DNA , Masculino , RNA Mensageiro/genética , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
16.
Echocardiography ; 24(10): 1099-104, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18001367

RESUMO

A new tool has been recently introduced to the echocardiography armamentarium, live/real time three-dimensional (3D) transesophageal echocardiography (TEE). In these cases, we describe our initial experience in 13 patients studied intraoperatively and in the echocardiography suite. This important technology promises improved anatomic definition, diagnostic confidence, and novel views of the complicated cardiovascular pathology encountered in common clinical practice.


Assuntos
Doenças da Aorta/diagnóstico por imagem , Ecocardiografia Tridimensional/métodos , Ecocardiografia Transesofagiana/métodos , Cardiopatias/diagnóstico por imagem , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
17.
Cardiol Clin ; 25(2): 319-25, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17765112

RESUMO

Evaluation of the mitral valve requires appreciation of its complex geometry. To accurately guide surgical interventions and describe pathology, three-dimensional transthoracic echocardiography (TTE) is an immense improvement over the cumbersome mental reconstruction required by two-dimensional approaches. Here we describe real-time, three-dimensional transthoracic techniques for assessing mitral regurgitation and mitral valve prolapse.


Assuntos
Insuficiência da Valva Mitral/diagnóstico por imagem , Prolapso da Valva Mitral/diagnóstico por imagem , Função Ventricular Esquerda/fisiologia , Humanos , Insuficiência da Valva Mitral/etiologia , Insuficiência da Valva Mitral/fisiopatologia , Prolapso da Valva Mitral/complicações , Prolapso da Valva Mitral/fisiopatologia , Reprodutibilidade dos Testes , Ultrassonografia
18.
Echocardiography ; 24(2): 166-73, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17313549

RESUMO

Due to reliance upon geometric assumptions and foreshortening issues, the traditionally utilized transthoracic two-dimensional echocardiography (2DTTE) has shown limitations in assessing left ventricular (LV) volume, mass, and function. Cardiac magnetic resonance imaging (MRI) has shown potential in accurately defining these LV characteristics. Recently, the emergence of live/real time three-dimensional (3D) TTE has demonstrated incremental value over 2DTTE and comparable value with MRI in assessing LV parameters. Here we report 58 consecutive patients with diverse cardiac disorders and clinical characteristics, referred for clinical MRI studies, who were evaluated by cardiac MRI and 3DTTE. Our results show good correlation between the two modalities.


Assuntos
Ecocardiografia Tridimensional , Ventrículos do Coração/anatomia & histologia , Ventrículos do Coração/diagnóstico por imagem , Hipertrofia Ventricular Esquerda/diagnóstico , Imageamento por Ressonância Magnética , Volume Sistólico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão
19.
Am J Physiol Heart Circ Physiol ; 292(6): H2607-12, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17237237

RESUMO

We have previously shown that 17beta-estradiol (E2) attenuates responses to endoluminal injury of the rat carotid artery, at least in part, by decreasing inflammatory mediator expression and neutrophil infiltration into the injured vessel, with a major effect on the neutrophil-specific chemokine cytokine-induced neutrophil chemoattractant (CINC)-2 beta. Current studies tested the hypothesis that activated rat aortic smooth muscle cells (RASMCs) express these same inflammatory mediators and induce neutrophil migration in vitro and that E2 inhibits these processes by an estrogen receptor (ER)-dependent mechanism. Quiescent RASMCs treated with E2, the ER alpha-selective agonist propyl pyrazole triol (PPT), the ER beta-selective agonist diarylpropiolnitrile (DPN), or vehicle for 24 h were stimulated with tumor necrosis factor (TNF)-alpha and processed for real-time RT-PCR, ELISA, or chemotaxis assays 6 h later. TNF-alpha stimulated and E2 attenuated mRNA expression of inflammatory mediators, including P-selectin, intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1, monocyte chemoattractant protein (MCP)-1, and CINC-2 beta. DPN dose dependently attenuated TNF-alpha-induced mRNA expression of CINC-2 beta, whereas PPT had no effect. The anti-inflammatory effects of DPN and E2 were blocked by the nonselective ER-inhibitor ICI-182,780. ELISA confirmed the TNF-alpha-induced increase and E2-induced inhibition of CINC-2 beta protein secretion. TNF-alpha treatment of RASMCs produced a twofold increase in neutrophil chemotactic activity of conditioned media; E2 and DPN treatment markedly inhibited this effect. E2 inhibits activated RASMC proinflammatory mediator expression and neutrophil chemotactic activity through an ER beta-dependent mechanism.


Assuntos
Anti-Inflamatórios/metabolismo , Quimiotaxia de Leucócito , Estradiol/metabolismo , Receptor beta de Estrogênio/metabolismo , Estrogênios/metabolismo , Miócitos de Músculo Liso/metabolismo , Neutrófilos/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Aorta/citologia , Aorta/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Quimiotaxia de Leucócito/efeitos dos fármacos , Relação Dose-Resposta a Droga , Estradiol/análogos & derivados , Estradiol/farmacologia , Antagonistas de Estrogênios/farmacologia , Receptor beta de Estrogênio/agonistas , Estrogênios/farmacologia , Feminino , Fulvestranto , Expressão Gênica/efeitos dos fármacos , Células HL-60 , Humanos , Inflamação/genética , Inflamação/metabolismo , Inflamação/prevenção & controle , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/efeitos dos fármacos , Neutrófilos/efeitos dos fármacos , Nitrilas/farmacologia , RNA Mensageiro/metabolismo , Ratos
20.
Menopause ; 14(2): 251-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17194962

RESUMO

OBJECTIVE: 17beta-estradiol (E2) negatively modulates neointima formation, leukocyte infiltration, and proinflammatory mediator expression after vascular injury in young (10-wk-old) ovariectomized (OVX) rats. Trials of E2 in elderly postmenopausal women have not confirmed a vasoprotective effect. This study tested the hypothesis that responsiveness to E2 is lost in injured arteries of aged (12-mo-old) OVX rats. DESIGN: E2- or vehicle-treated OVX rats underwent balloon injury of the carotid artery and were killed after 2 weeks for morphometric examination of arteries, after 24 hours for assessment of leukocyte infiltration, and after 2 hours for quantification of proinflammatory mediator mRNA expression. RESULTS: Neointima formation was significantly reduced in aged compared with young vehicle-treated rats. E2 treatment had directionally opposite effects on intima/media ratios in aged (+75%) and young (-40%) rats. Injury induced increases in infiltrating total leukocytes, neutrophils, monocytes/macrophages, and expression of proinflammatory mediators in arteries of aged rats; E2 had no effect on these inflammatory responses to injury. Estrogen receptor alpha and beta protein expression were similar in carotid arteries of young and aged rats on immunofluorescence testing. CONCLUSIONS: Aged OVX rats lose the vasoprotective and anti-inflammatory responses to exogenous E2 seen in younger animals. These results may be relevant to the lack of vasoprotection observed in outcome trials of estrogen therapy in postmenopausal women.


Assuntos
Lesões das Artérias Carótidas/prevenção & controle , Quimiotaxia de Leucócito/efeitos dos fármacos , Estradiol/farmacologia , Mediadores da Inflamação/metabolismo , Envelhecimento , Animais , Lesões das Artérias Carótidas/patologia , Modelos Animais de Doenças , Estradiol/administração & dosagem , Estradiol/uso terapêutico , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Leucócitos/efeitos dos fármacos , Ovariectomia , Ratos
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